Conventionally, there is an auto white balance technology of adjusting a white balance of a pickup image obtained by picking up an object. Color of the object of the pickup image changes depending on light of a light source that illuminates the object. In the auto white balance technology, based on a pixel value of the whole of the pickup image, gains for respective color components are calculated, and the color of the pickup image is adjusted.
In the auto white balance technology, when the object is under a plurality of light sources, the white balance is adjusted based on light of a dominant light source in the whole of the pickup image, and the white balance in a region receiving light of another light source is lost, in some cases.